Gardening for Butterflies

  • Variable checkerspot butterflies need nectar for food while they search for the appropriate host plant to lay their eggs on. Photo: Marc Kummel
  • Butterflies will often deposit their eggs on the underside of a leaf where they are more protected. Photo: Marc Kummel
  • Caterpillars will consume several plants but their principal host plant is sticky monkeyflower. Photo: Marc Kummel
  • An adult butterfly will emerge from the chrysalis formed by the caterpillar. Photo: Marc Kummel

The lovely winged jewels we call butterflies are the pioneering and reproductive life stage of an insect that goes through 3 other distinct stages: eggs, larvae (caterpillars), and pupae (chrysalids). The adult stage, the butterfly, is technically called the imago. About eighty percent of all insects are holometabolus, which is a way of partitioning resources, so that each life stage does not compete with any other. Your habitat garden needs to provide for the needs of every life stage in order for there to be butterflies.

The purpose of a butterfly’s often short life “on the wing” is simply to find a mate and the host plant on which to lay the eggs of the next generation. They will be looking for the plant that their hatched larvae will eat; many butterfly species are extremely choosy about what plant that is. The adult butterfly will need nectar for energy as she hunts for her special host plant. If you are interested in attracting a specific type of butterfly, check the handout at right, Butterfly Larval Host Plants, to learn some of the appropriate plants.

To get a good indication of which butterfly species are already present in the general area of your garden, start with specimens of flowering plants that are noted as really good nectar sources, and then observe the butterflies that come into your garden to feed. Buddleias, verbenas, and lantana, though not native, bloom for a long period of time and are loved by butterflies. Flowers in the composite family (aster, sunflower, or daisy), offer a landing pad when fully opened, which is important for the larger butterflies like the Monarchs. Flowers in the composite family are composed of hundreds of individual disc flowers, and petal flowers, and each of these tiny flowers provides nectar and pollen, thus providing a lot of food energy in one place!  If you can, allow “managed” populations of weeds such as Italian thistle, English plantain, and cudweeds, which are favored larval host plants of some beautiful butterfly species.

Butterflies are not important pollinators of plants, but their beauty certainly adds to the charm of any garden!

The Family Asclepiadaceae

The genus name, Asclepias, derives from the Greek god and healer, Asclepios. The Roman god of healing and medicine was named Aesculapius, and there was good reason for naming this genus of plants after this god. The plants contain organic compounds that have been used to treat various ailments and conditions of the heart and nervous systems, as well as the stomach and intestines. All parts of the plant contain cardiac glycosides and cardenolides, specifically one called oleandrin, which are concentrated in the milky latex sap.

Our “Torties”: California Tortoiseshell Butterflies

I’m seeing more California Tortoiseshells (Nymphalis californica) than usual; it’s a high population year for these butterflies! During the summer months, this species is in the mountains at much higher elevations and then they migrate back down to the lowlands by October. Here, they over-winter as adults, and in early March, mate and lay eggs on ceanothus, right around the time of bud break, while the leaves are still young and tender. By late May, the adults emerge and start flying to higher elevations in the Coast or Klamath ranges, or towards the Sierra Nevadas.

Useful Nonnative Weeds

I’d bet that we’re all pretty happy that the rainy season is over and cherishing the beautiful sunny days. With a good layer of mulch to help retain moisture in the soil, plus the warm days, plants are now putting on growth that can almost be measured day by day!

Snowberries and A Bumblebee Mimic

I’m experiencing a love-hate relationship with the rains as they continue, with so few dry days in between for the outdoor activities that are such a big part of my life. I’ve measured more than 30 inches here on our Novato hillside since January first!  

The scarcity of truly dry days in between poses all sorts of frustrations for the dedicated gardener; it’s great to have the rains, and this is the time of year to plant, but it’s not good to work the soil when it’s totally soggy.

Propagating from Seeds

Making Space for Weeds

The Flickers have now left my oak woodlands and moved to higher elevations in the Coast Ranges; I’ll look forward to seeing them again when we’re camping in the forests this summer. Meanwhile, the Tree Swallows are here already and I’m waiting to hear the first calls of the Ash-throated Flycatchers as they arrive from wintering grounds in Baja California. For the last five or six years they have shown up about the fifth of May, and by June are raising a brood in the nesting box hung in an old Coast Live Oak.

Milkmaids in Abundance

Even if it’s just for an hour or two, I make time to do some work in my garden every single day, and my favorite time to be outside is at dusk when all sorts of creatures are stirring. Since my tasks, like weeding or potting up seedlings, are often simple and somewhat repetitive, I’m in a meditative state and absorbing all that goes on around me.

Some Other Common Brushfoots (Nymphalidae)

The Mourning Cloak  (Nymphalis antiopa) is fairly common in Marin, and adults can be seen flying almost any time during the year. This species is also found in Europe; on the British Isles it is known as the Camberwell Beauty, and considered the rarest of British butterflies. In Marin we see this butterfly throughout the year; in more inland areas the adults migrate to higher altitudes in summer, and disperse again downslope in the fall.

Acmon Blue Butterflies

The Acmon Blue Butterflies (Plebejus or Icaricia acmon) are fairly common and more widespread than some of the other gossamer wings (Lycaenidae). The Acmon Blue has a much longer flight period than many other blues; it visits gardens and can be seen in open fields and even along roadsides.